Shingled magnetic recording / Hybrid Drives vs Large compiling tasks

cyent · 05-12-2021, 10:11 PM

So my company got suckered into buying a bunch of these things...

https://en.wikipedia.org/wiki/Shingl...etic_recording

In particular a Seagate hybrid ssd variant.

I'm convinced the thing is slowing down and slowing down...

Anybody have any tricks io-schedulers tweaks... to try recover performance?

My work load is basically running as many gcc compiles as I have cpu cores for...

business_kid · 05-13-2021, 08:03 AM

They are aimed at density rather than speed. Writing might be faster than rewriting, so they did their initial bit quick, and are now slowing down to a lower normal Also, I'm sure the overlaps have to be verified.

I agree, you were suckered, but compiling isn't disk intensive if you don't have swap there. As for your drives, why not stick them on Ebay?

EdGr · 05-13-2021, 09:48 AM

Here are two things you can try.

Prefetch the source files into the kernel's disk cache.

Code:

find sourcedir -type f -exec cp '{}' /dev/null \;

Run several times the number of jobs as the number of CPU cores. If a job gets blocked waiting for a disk read, other jobs still can run.
Ed

cyent · 05-13-2021, 04:03 PM

Yip. Already did that a few years back... I called it the most useful program I ever wrote that imperceptibly does nothing.

I also nice -19 ionice -c 3 it so it doesn't impact the desktop.